B.D. Silliman Professor of Physics
B.S., Clarkson College of Technology
Sc.M., Ph.D., Brown University
Steve Feller’s research in physics centers on the atomic structure and physical properties of glass. Feller’s group work on determining the atomic structure of glass and its relationship to the physical properties. They make new-to-the-world glasses with unusual compositions and use a variety of in-house methods that can cool liquids at 100,000 oC/s or heat our samples to nearly 3000 oC. Feller's Group determines the atomic structure using a number of modern techniques: Nuclear Magnetic Resonance, Neutron Scattering, Raman Spectroscopy, Infrared Spectroscopy and modern calculational tools.
They compare the structure to a number of important physical properties including: density and packing efficiencies; thermal properties including the glass transition temperature, the crystallization temperatures, the specific heat; the velocity of sound in glass and the various strength parameters. The comparison is done using computer models, many of which are developed in house.
After teaching at Coe College for 39 years, Feller does full-time research with students. Since 1979, he worked with over 150 students, published over 150 papers in the refereed literature of the field. He has also edited a number of books on glass science. Steve and his students have given over 200 presentations at well over 100 national and international conferences. Funding from 93 grants for over $8,200,000 has been secured since 1983 from a large number of foundations including the National Science Foundation. He also has a research-level interest in numismatics, the study of the history of money. In this area he has published over 100 articles and several books.
He has been honored a number of ways including: Society of Glass Technology (SGT) Centenary Fellow (2016). Fellow of the American Ceramic Society (2003) and the British Society of Glass Technology (2003), Physics Club Chapter Advisor of the Year by the national Society of Physics Students (2000), Distinguished Iowa Scientist by the Iowa Academy of Sciences (1999), Fulbright Scholar (1996), Iowa Professor of the Year (1995) by the Carnegie Foundation for the Advancement of Teaching. American Physical Society Prize to a Faculty Member for Research in an Undergraduate Institution (1993). C.J. Lynch Prize as Teacher of the Year (1993).
From 1996-2002 he served on the national board of the Society of Physics Students. In 2002 he was elected the president of Sigma Pi Sigma, the national physics honor society, a position he was reelected to in 2004. He was the chair of the organizing committee of the 2008, 2012, 2016 and 2019 Sigma Pi Sigma Congresses.
- Book chapter, "Borate Glasses: Structure, Properties, and Uses" for the Springer Handbook of Glass (2019).
- “Structure of TeO2 Glass: Results from 2D 125Te NMR Spectroscopy,” Journal of Non-Crystalline Solids 513 183 (2019).
- “Molecular dynamics simulation of an anomaly in the temperature widths of the glass transition for low modifier alkali borate glasses,” Physics and Chemistry of Glasses - European Journal of Glass Science and Technology Part B 60 1 (2019).
- “A 10B NMR Study of Tetrahedral Borons in Ring Structured Borates,” Physics and Chemistry of Glasses - European Journal of Glass Science and Technology Part B 60 1 (2019).
- “Topological Constraint Model of Alkali Tellurite Glasses,” Journal of Non-Crystalline Solids 502 15 (2018).
- “Properties and Structure of Glassy TeO2 and Binary Potassium and Boron Tellurites,” Journal of Undergraduate Research in Physics XXVII 6 (2018).
- “Composition Dependence of the Short Range Order Structures in 0.2Na2O + 0.8[xBO3/2 + (1-x)GeO2] Mixed Glass Former Glasses,” Journal of Non-Crystalline Solids 500 61 (2018).
- “A 44 Year Search: How do the Fundamental Physical Properties of Borate Glass Reveal its Underlying Atomic Structure: An Adventure with Undergraduates,” Physics and Chemistry of Glasses - European Journal of Glass Science and Technology Part B 59 4 (2018).
- “Short-Range Structure of TeO2 Glass,” Journal of Physical Chemistry C 121 50 (2017).
- “An anomaly in the glass transition width trends of alkali borate glasses at low modifier loadings,” Physics and Chemistry of Glasses - European Journal of Glass Science and Technology Part B 58 5 (2017).
- “Elastic Properties and Short-Range Structural order in Mixed Network Former Glasses," Physical Chemistry Chemical Physics 19 (2017).
- “The Germanate Anomaly in Alkaline-Earth Germanate Glasses,” Journal of Physical Chemistry C 121 17(2017).
Fran Allison and Francis Halpin Professor of Physics
B.A., Coe College
Ph.D., Vanderbilt University
Dr. Affatigato’s personal research interests lie in the area of the optical and electrical properties of glasses and the relationship between such properties and the structure of the glass.
Affatigato’s research groups primarily work on the use of laser light in the manufacture and study of glasses. In one project, for instance, laser light is used to melt a glass bead while it is being levitated by a gas. In another, Raman spectroscopy is used to look at changes in the structure of glasses. In a third project, student researchers look at the molecules that come off a glass as it is hit by UV laser light. Dr. Affatigato and his students also work on projects such as development of glass that kills bacteria, or developing conducting glasses that can be used in particle detectors. Mario and his students also map the surface topography of glasses using atomic force microscopy.
- "Structural and optical properties of cerium oxide doped barium bismuth borate glasses," Journal of Non-Crystalline Solids 499 1 (2018).
- "Structural and optical properties of rare-earths doped barium bismuth borate glasses," Journal of Non-Crystalline Solids, 481 1 (2017).
- “Control of self-powdering phenomenon in ferroelastic β′-Gd2(MoO4)3 crystallization in boro-tellurite glasses”, Journal of Non-Crystalline Solids, 501 1 (2017).
- “Long Afterglow In Hexagonal SrAl2O4:Eu2+, Dy3+ Synthesized By Crystallization Of Glass And Solidification Of Supercooled Melts,” Journal of Luminescence 177 (2016).
- “Measurements of the Rate Capability of Various Resistive Plate Chambers,” Journal of Instrumentation, 10 10 (2015).
- “Electronically Conductive Vanadate Glasses for Resistive Plate Chamber Particle Detectors,” International Journal of Applied Glass Science, 1 8 (2015).
Associate Professor of Physics
B.S., Middle East Technical University
Ph.D., University of Iowa
Ugur's research area expands from experimental high energy physics to computational biophysics. He is involved in Compact Muon Solenoid (CMS) experiment at the Large Hadron Collider (LHC) of CERN, in Geneva, Switzerland. Ugur is also member of SELEX and MIPP experiments at Fermi National Laboratory, in Batavia, Illinois. His main expertise is on radiation hard particle detectors. His recent projects include novel glass detectors, such as neutron detectors for homeland security, 3 dimensional dosimeters, and proton imaging detector. Ugur’s group develop the novel materials, design and perform the simulations of these detectors.
Ugur's secondary research area is computational biophysics. His group use various molecular dynamics simulation techniques to determine the mechanisms of membrane proteins. Ugur and his students are recently simulating P-Glycoproteins, Urea and Ammonia channels, and AQP0-CaM system.
- "A glass neutron detector with machine learning Capabilities," Journal of Instrumentation, JINST_021P_0319, (2019).
- "Use of machine learning in CARNA proton imager,” Proceedings of the Medical Imaging 2019: Physics of Medical Imaging (2019).
- "Luminescence of Ce-doped aluminophosphate glasses," J Mater Sci: Mater Electron, https://doi.org/10.1007/s10854-019-01301-4, (2019)
- "CARNA – A compact glass proton imager," Proceedings of the 2017 IEEE Nuclear Science Symposium and Medical Imaging Conference, DOI: 10.1109/NSSMIC.2017.8533076 (2018).
- "Investigation of Ce3+ luminescence in borate-rich borosilicate glasses," Journal of Non-Crystalline Solids 471 1 (2017).
- "Radiation hard elastomer scintillators for a new generation of particle detectors," Journal of Instrumentation 12 (2017).
- “High-density scintillating glasses for a proton imaging detector,” Journal of Optical Materials, 68 58 (2017).
Assistant Professor of Physics
B.S., Bosphorus University
M.S., Ph.D., University of Iowa
Firdevs’ main research interest is the ionosphere around the planets. Dr. Duru’s group analyzes the data coming from the spacecrafts Mars Express, MAVEN, Juno and Cassini.
- "Electron Density Profiles in the Upper Ionosphere of Mars From 11 Years of MARSIS Data: Variability Due to Seasons, Solar Cycle, and Crustal Magnetic Fields," Journal of Geophysical Research: Space Physics 124 4 (2019).
- "Radiation Shielding Capabilities of Glasses with Potential Applications in Spacecraft and Laboratories," APS March Meeting 63 1 (2018).
- "Response of the Martian ionosphere to solar activity including SEPs and ICMEs in a two-week period starting on 25 February 2015," Planetary and Space Science 145 1 (2017).
- Book Chapter “Solar wind interaction and atmospheric escape” for the The Atmosphere and Climate of Mars (2017).
- “Post Situ Neutron and Gamma Radiation Damage Tests on Different Quartz Types,” Journal of Instrumentation 11 (2016).
- "Night Side Ionosphere of Mars Studied with Local Electron Densities: A General Overview and Electron Density Depressions", Journal of Geophysical Research-Space Physics 116 (2011).
- "Ion Energization and Escape on Mars and Venus," Space Science Reviews 162 (2011).
- "The induced magnetospheres of Mars, Venus, and Titan," Space Science Reviews 162 1-4 (2011).
Caio Barca Bragatto
Assistant Professor of Physics
B.S., University of Sao Paulo
M.S., Ph.D., Federal University of Sao Carlos
Postdoctoral researcher, University of Jena
Caio Bragatto is an Assistant Professor of Physics at Coe College (Iowa, USA). Bragatto earned his B.S. degree in Industrial Chemistry from the Universidade de São Paulo (São Paulo, Brasil), and his Masters and Ph.D. degree in Materials Science and Engineering from the Universidade Federal de São Carlos (São Paulo, Brasil). Before being hired as an Assistant Professor, Bragatto worked as a research assistant at the Otto-Schott Institut für Materialwissenschaft (Thüringen, Germany). He specialized in ionic conductivity of glasses, focusing especially on unveiling the mechanisms behind the phenomena and working on a universal model to predict this property. Ionic conductive glasses are used mainly as electrolytes in solid-state batteries and sensors. To do so, Caio conducts both laboratory and computational experiments, complementing one part with the other.
- "Topological Origins of the Mixed Alkali Effect in Glass," The Journal of Physical Chemistry B 123 34 (2019).
- "Charge carrier mobility of alkali silicate glasses calculated by molecular dynamics," Frontiers in Materials | Glass Science 6 121 (2019).
- "Mixed-modifier effect in alkaline earth metaphosphate glasses,” Journal of Non-Crystalline Solids 481 447 (2018).
- “Dissociation equilibrium and charge carrier formation in AgI–AgPO3 glasses,” The Journal of Chemical Physics C 121 (25) 13507 (2017).
- “Structural relaxation in AgPO3 glass followed by in situ ionic conductivity measurements,” Journal of Non-Crystalline Solids 437 43 (2016).
Professor of Physics, Emeritus
B.A., M.S., University of Chicago
M.S., Ph.D., University of Iowa
James Cottingham performs research on musical acoustics. His specialty is free-reed instruments, including several from around the world, especially from Southeast Asia.
- "Initial transients in free reed instruments: A survey of experimental results," The Journal of the Acoustical Society of America 145 1676 (2019).
- "High frequency cavity modes of a Helmholtz resonator excited by an air jet," The Journal of the Acoustical Society of America 145 1709 (2018).
- "The Technical Committee on Musical Acoustics: Diverse membership with a common interest," The Journal of the Acoustical Society of America 143 1733 (2018).
- "The barbershop sound: The characteristic timbre of the male barbershop quartet," The Journal of the Acoustical Society of America 143 1843 (2018).
- "Early history of the accordion family: Where did all the accordions come from?," The Journal of the Acoustical Society of America 142 1570 (2017).
Adjunct Assistant Professor of Physics
B.S., Ph.D., University of Iowa
James Wetzel is currently affiliated with both CERN and Fermi National Accelerator Laboratory where he is actively involved in the field of experimental particle physics. His main interest is in the design, simulation, construction, and finally testing of detectors, in particular hadronic and electromagnetic calorimeters.
He has a passion for space and astronomy and has brought that to Coe by designing a general education astronomy course with lab component, which he loves to teach!
“Brightness and uniformity measurements of plastic scintillator tiles at the CERN H2 test beam”, Journal of Instrumentation 13 (2018).
“Using LEDs to Stimulate the Recovery of Radiation Damage to Plastic Scintillators”, Nuclear Instruments and Methods in Physics Research Section B: Beam Interactions with Materials and Atoms 395, 15 (2017).
“Liquid Scintillator Tiles for Calorimetry”, Journal of Instrumentation 11 (2016).
“Search for heavy Majorana neutrinos in e±e±+jets and e±μ±+jets events in proton-proton collisions at √s = 8 TeV”, Journal of High Energy Physics 04 (2016).
“Radiation Damage and Recovery Properties of Common Plastics PEN and PET Using a 137Cs Gamma Ray Source Up To 1.4 MRad and 14 MRad”, Journal of Instrumentation 11 (2016).
"Characterization of photomultiplier tubes in a novel secondary ionization mode for Secondary Emission Ionization Calorime- try”, Journal of Instrumentation 11 (2016).